Galaxy S2 shutting off in idle mode

Galaxy S2 shutting off in idle mode

Recently, I noticed that my phone shuts off while in sleep mode. This just happens when I don't check it for a while and the display is turned off. When I do go to check my phone, it's unresponsive, even if I hold down the power button. So far, I've had to remove the batter every time this has happened in order to reboot it.

I just don't get what the issue is. I'm probably missing phone calls because I'm not even aware that my phone is turning off. I feel like after the ICS update my phone has had issues. I already performed a factory reset last week since I was having a problem with the notifications not ringing and vibrating, and now, this is happening on top of that.

If anyone has any suggestions, that would be greatly appreciated.

I have a Samsung Galaxy S2 i777.

Oh, and another thing, I noticed that my batter is at 95-100% before it shuts off by itself, and once it boots up again it's down to 85-89%. I also feel like it might be an issue with overheating: I noticed that my phone feels hot after I've been using it for a while, like texting or using the internet, and then I set it down to do other stuff when I notice that it's turned off. My phone usually feels really hot too, and the case I have for my phone probably does not help either.

Re: Galaxy S2 shutting off in idle mode

Same issue with my s2 it is really big problem.

I had to take the flight in morning and put alarm for 4.30 am . The phone turned off in night i checked full battery was dere at 10.30 pm and i missed the flight.i took a lesson that better use an alarm clock and dint be dependent on phonefor alarm.

Battery LIfe Update

Thought I'd post an update on my battery life post-fix. I have easily been able to get 3 days on a charge now.

BUT... here's why... I don't charge the phone, I swap batteries and put the used one in a wall-charger.

I did some experiments and charging the phone gave me approx. ONE day of use. Use my spare battery swap routine and I have gotten as much as FIVE days. Granted, they were really light use days... but still.

So, charging the phone is an occasional necessity. But, when ever I can and most of the time, I do the swap and it is GREAT!